Thanks to its versatility, Buchs can be found in almost every garden. However, it is also a very sensitive plant that reacts just as quickly to suboptimal environmental conditions as it does to fungal or pest infestation. Brown spots on the leaves and shoots are quite common and have very different causes.
Brown spots can have various causes
Causes of brown spots on leaves and shoots
If you discover such spots, you don't have to immediately think of the dreaded box tree dying. There are many other causes that are far less threatening. Cold temperatures, for example, cause yellow leaves, as this is how the plant tries to protect itself from sub-zero temperatures. In this case, it will turn green again all by itself. We have compiled other causes for you in the following overview.
Sunny location
If your boxwood is in full sun, the leaf spots indicate simple sunburn. Incidentally, these specimens are particularly threatened by dehydration and lack of nutrients, which is always a consequence of the lack of water. Replant the plagued boxwood to a more suitable location and ensure sufficient - not excessive! - Supply of water and nutrients.
pest infestation
Furthermore, some pests first cause leaf spots before they themselves become clearly visible. For example, if spider mites have settled, this is initially indicated by yellowish speckles on the leaves. Only later do they turn brown and fall off. The gall midges that are often found on box trees also cause similar damage. Here, however, the typical gall bladders form on the underside of the leaf.
fungal diseases
Last but not least, of course, some fungal diseases cause leaf spots. The dreaded boxwood dieback, for example, shows itself in its early stages by the characteristic orange to brown spots on the leaves. Soon after, they fall off and the instincts die off. If, on the other hand, red-brown, bumpy spots appear, it is boxwood rust. The white fungal growths on the underside of the leaves are also typical here.
What to do in the event of an acute fungal disease?
In the event of an acute fungal disease, you should act as quickly as possible to limit the damage. These measures are essential:
- vigorous pruning into healthy wood
- Never dispose of clippings in the compost or leave them lying around
- dispose of with household waste or incinerate instead
- Rake up and discard fallen leaves and leaves lying on the ground
- Carefully disinfect cutting tools before and after cutting
tips
Incidentally, once boxwood dieback has occurred at a location, no more boxwood should be planted here for several years. The fungal spores survive in the soil for a very long time, so that only replacing the soil can help.